农业生态系统养分循环再利用作物产量增益的地理分异

Geographic differentiation of yield-increase efficiency caused by recycled nutrients in agro-ecosystems

根据 3个地点中长期田间试验联网比较研究发现 ,保持养分循环再利用可明显减少作物产量的年际波动 ,使作物具有较好的产量稳定性。农业生态系统养分循环再利用的产量增益与化肥施用和所处气候区的热量因素有关。在无化肥的前提下 ,保持 80 %循环率养分循环再利用的平均粮食增产量从北向南分别是 :海伦 2 62kg·hm-2 ( 14年平均 ) ,沈阳 95 6kg·hm-2 ( 12年平均 ) ,桃源 3 0 63kg·hm-2 ( 11年平均 ) ;在施用N、P化肥基础上保持养分循环再利用其增产量分别为 :海伦2 5 0kg·hm-2 ( 14年平均 ) ,沈阳 489kg·hm-2 ( 12年平均 ) ,桃源 15 3 1kg·hm-2 ( 11年平均 )。表明养分循环再利用这一生态过程所产生的效应有着明显的地理分异规律。据此可以认为 ,保持农业中养分循环再利用对于热量充沛的我国南方热带、亚热带地区尤为重要。

The results of field trials at three sites in different parts in China showed that the fluctuation of yield caused by the different climate years was significantly decreased by the application of recycled nutrients. The results also indicated that the yield increase caused by recycled nutrients in agro-ecosystems was significantly affected by the application of chemical fertilizer and the thermal condition of climate. In the case of no chemical fertilizer, the average increase of crop yield caused by recycled nutrients with 80% recycling rate ranged from 262 kg·hm^(-2) (average of fourteen years) at Hailun Station (in middle-temperate zone) to 1956 kg·hm^(-2) (average of twelve years) at Shenyang station (in middle-temperate zone) and 3063 kg·hm^(-2) (average of eleven years) at Taoyuan station (in subtropical zone) respectively. All the results showed that there was a remarkable geographic differentiation of yield-increase efficiency caused by recycled nutrients.